1. Field of the Invention
The invention relates to a radio receiver, in particular, a VHF receiver, comprising
a receiver stage for receiving and demodulating a radio signal, PA1 an evaluation stage for evaluating the quality of the received radio signals in accordance with predetermined receiving criteria, PA1 a storage stage for storing data about at least transmitter frequencies and/or transmitter names of stations whose radio signals meet said predetermined receiving criteria, PA1 an operating element for setting the receiver stage so as to receive the radio signal of a desired station, PA1 a display element for displaying information about at least the desired station, which information is derived from the stored data, and PA1 a control unit for controlling at least the receiver stage, the storage stage and the display element according to the operation of the operating element, and for controlling the receiving quality evaluated by the evaluation stage. PA1 when the receiving quality of the radio signal of a desired station currently does not, or no longer, meets the predetermined receiving criteria, the relevant data in the memory stage are erased and the receiver stage is tuned to receive the radio signal of a new, desired station; preferably, the new, desired station broadcasts the same program as the hitherto desired station, and the data of the new, desired station replace the erased data of the hitherto desired station in the memory stage; it is particularly preferred that the new desired station is found by autoscanning of the receiver stage; PA1 when the desired station is replaced by a new desired station by operating the operating element, it is checked whether the radio signal of the new, desired station meets the predetermined receiving criteria; if so, the data in the memory stage of the control unit are replaced by the data of the new, desired station; preferably, the transmission frequency of the new, desired station is found by autoscanning of the receiver stage; PA1 before at least the receiver stage of the radio receiver is turned off, the data of the stations having radio signals which meet the predetermined receiving criteria are stored again in the memory stage by the control unit by means of an autoscanning operation for a frequency range which is as wide as possible, preferably all frequencies to which the receiver stage can be tuned;
2. Description of the Related Art
European Patent specification EP-A-95564 discloses a mobile radio receiver, in particular a car radio with direct program selection, which comprises, in an operating panel, program display surfaces and, associated therewith, selection keys for selecting the programs displayed. To obtain a small well laid-out operating panel which displays a plurality of radio programs receivable at different locations of the radio receiver, exchangeable program displays can be reproduced on the program display surfaces, this exchangeable program representing an up-to-date selection of the programs transmitted by stations having receiving quality at the current receiver location which satisfy predetermined receiving criteria, for example, a predetermined received field strength.
This known radio receiver comprises a random-access coupling memory (RAM) having a number of memory locations, each memory location being permanently allocated to one of the program display surfaces with the associated selection key. station-defining quantities of the stations which can be received at the receiver location and which satisfy the predetermined receiving criteria, are allocated to this coupling memory. This allocation is continuously updated. Said continuous update of the memory contents in response to a change in receiver location requires, in the known radio receiver, a circuit whose essential components are a second receiver member having an automatic station finder to permanently search stations which can be received, a station identification device to identify the station found and a receiving-quality control device to check the receiving quality of the station found. The known radio receiver comprises said components in addition to the receiver member necessary to receive and reproduce the desired programs.
U.K. Patent Application GB-A-2 213 336 discloses an RDS radio receiver with display of alternate frequencies of specific radio stations. This radio receiver comprises a tuning stage which is operable over at least two frequency bands. Connected to this tuning stage is a data decoding means for decoding data signals transmitted together with a received radio signal. The received radio signal is broadcast within a first frequency band, for example, the medium waveband. The data signals comprise data relating to radio signals within the first frequency band and data relating to radio signals within the other frequency bands, for example, the long waveband. Connected to the data decoding means is a data storing means for storing the data signals relating to the other frequency bands. The data, which relate to a selected radio signal, are at least partly displayed on a touch-sensitive display. In this manner, RDS data, which are transmitted at frequencies on which the RDS system operates and which relate to frequencies, in particular, for the same radio program at which no RDS signal is transmitted, are stored by means of the receiver arrangement. In this way, a selection of all, or at least a part, of the frequencies relating to a radio program can be displayed, on the display and the desired frequency relating to the desired radio program can be selected.
The radio receivers in accordance with the state of the art are, on the one hand, constructed in a relatively complex and expensive manner and/or, on the other hand, exhibit a limited range of applications. For example, particularly in the case of daily commodities manufactured in large numbers, such as a radio receiver, the use of two concurrently operating complete receiver elements (tuner), of which only one is necessary during the major part of the service life of the radio receiver, leads to a very high and uneconomical extra expenditure. On the other hand, the above-described display devices are also very expensive and, in particular, require much space on the front side of the radio receivers where, in general, all operating elements of such a radio receiver are arranged. Particularly in the case of radio receivers for use in motor vehicles, where the standardized dimensions of the housings cause the dimensions of the front surfaces of the radio receivers to be bound to narrow limits, every extensive operating element causes great constructional problems. In addition, the operation by the listener becomes more complex as the number of operating elements increases. On the other hand, also in the case of radio receivers for use in other fields of application, the ratio of the space occupied by the operating elements to the space occupied by the other elements increases as a result of the miniaturization of the components, so that a simplification of the operating elements, without adversely affecting the ease of operation as the number of power characteristics of such radio receivers increase, is urgently needed.